Synthesis of Spinel LiMn_20_4 Powders by the Drip Pyrolysis in Fluidized Bed Reactor

摘要

A simple technique has been developed to directly produce fine ceramics powders from liquid solution by drip pyrolysis in a fluidized bed reactor.Using this technique,the preparation of lithium manganese oxides LiMn_2O_4,which are the most promising cathode materials for lithium ion battery,has been carried out for various superficial gas velocities U_o = 0.30-0.91 m/s,concentrations of precursor solution C_o = 0.45-4.50 mol/dm~3 and static bed heights L_s = 50-150 mm.The as-prepared samples exhibited a pure cubic spinel structure without any impurities in the XRD patterns,and the chemical composition of as-prepared powders showed in a good agreement with the one of precursor solution.The as-prepared sample was used as cathode active materials for lithium-ion battery and their charge/ discharge properties have been investigated.Test experiments in the electrochemical cell Li|lM LiClO_4 in PC|LiMn_2O_4 demonstrated that the sample,prepared by the drip pyrolysis method and then calciend at 750 deg C for 4 h in the air,was a promising cathode material for 4 V lithium-ion batteries.